Elaborate machinery and procedures have been employed to produce envelopes in a continuous stream, i.e., with adjacent envelope assemblies interconnected to form a series. I have discovered that, by virtue of employing discrete envelope backs laid down on a continuous web equipped with line holes, a speedy and reliable envelope stream can be produced and, by spacing the envelope backs, a continuous stream of return envelopes can be provided which is readily integrated into a high speed mailer operation.
Other objects and advantages of the invention may be seen as this specification proceeds.